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Carl Reynolds and Paul Tymann

"Schaum's Outline of Principles of Computer Science"

When only a hundred academics
used the Internet regularly, there was more opportunity to try new protocols and approaches.
Now with millions of people, thousands of businesses, and billions of dollars dependent on current
protocol definitions, it is almost unthinkable to disturb the protocol infrastructure.
Our ???ossified??? protocols support the business, shopping and communications of end users of
the Internet.
7.3 Using Google or some other source, find a list of other ???well known ports??? in networking besides port 80.
See http://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers
7.4 Most Internet communications use the TCP protocol, but some do not. Some communications use only
the IP protocol. Another name for the IP protocol is user datagram protocol (UDP). Why would an
application choose to use UDP? Can you think of a category of applications that might prefer UDP?
UDP is a low-overhead, high-speed protocol. By doing away with checks for out-of-order, duplicated,
or lost packets, UDP offers higher performance. Many networks have extremely low error rates
anyway, so the cost of reduced reliability may be small, and the gain in speed substantial.
Audio and video streams may well be communicated via UDP.


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